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From my experience of a zwo with an AR only window and a refractor, you are likely to want an IR cut filter (Which in most cases I have actually seen is a UV-IR cut) or you could see some spectacular reflection issues.
A quick rundown on the various filters.
Luminance - A broadband filter which more or less passes everything from the near infra-red to the near ultravoilet. The ZWO "IR" filter cuts both IR and UV ends, I would consider it to be a luminance filter. You can get these in various passbands, my old SCT had some real reflection issues so I used an Astronomik L2 filter which cut more out of the ends of the spectrum and improved the situation markedly.
Red-Green-Blue - Broadband filters which pass only the intended section of the spectrum. Narrowband filters - "Notch" filters which pass only a very specific wavelength, they come in various passband widths, generally the tighter the passband, the more they cost! The very narrow pass filters can be used to pick off elements which emit light at very similar wavelengths. With varying degrees of usefulness you can use all of these with mono sensors as they are generally intended, or with OSC colour sensors.
Multi band pass filters (like the L Extreme Martin mentions) these pass two or more individual "Notches" so you can for instance image in Hydrogen Alpha and Oxygen 3 at the same time, they are only particularly useful with colour sensors where the HA and Oiii will show up on different colour pixels.
If I were putting my money down in your situation I would put it together first and make sure it is able to come to focus, then put a very bright star in the frame and see if it is showing any reflection oddities, if it does, some form of IR cutting filter is likely to help.
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